How to cut sorbothane?


I recently read a glowing review of Herbie's Big Fat Discs, which are 5/16" thick by 1 5/16" diameter sorbothane discs. So, I did some research and I found a huge variety of sorbothane sheets available at McMaster-Carr. I bought a 12"x12" by 1/4" sheet of 40 durometer sorbothane for $29.

Does anyone have a clever and easy method for cutting discs out of this sheet other than scissors? I was thinking of a sharpened cookie cutter type thing as a tool which could be hammered down on the sorbothane, effectively cuttting a disc...

BTW, I can get 8 discs out of this $29 12"x12" sheet (with useful scrap left over), and 8 Herbie's Big Fat Discs would cost just under $90.
tvad
Oh my gosh. I forgot to add what Newbee pointed out. A lot of thermoset polyurethanes outgas forever and will leach out oils and plasticizers. They also react with a certain classes of thermoplastics in a very unpleasent way (melt the thermoplastic). They can also stain your carpet. Cut a polyethylene (ziplock) bag in a slightly larger diameter to place underneath the pucks. Shouldn't be any reaction. Sorry!
Well, I received the 40 durometer sorbothane and looked again at my
VR4 cabinets...and voila...the top cabinet is essentially supported by four
small sorbothane footers. I had remembered them as being harder
rubber. Since the sorbothane I purchased is the same height as the VR4
footers, I'm going to bag that idea unless I decide to return what I
purchased for a thicker piece. In the meantime, I'm using the
12"x12" sorbothane sheet under my Paradisea DAC.

As for cutting the sorbothane, I've been watching arch punches on E-Bay
for nearly three weeks. I've lost a couple of auctions. At this point, I
believe I can likely cut the 5/16" thick sorbothane with a pair of
scissors.
Finally purchased a 1 1/2" arch punch on E-Bay. Hopefully, this will work to cut the 5/8" sorbothane sheet.

I'll have a few more discs than I require. If you might be interested in some, send me an email. They won't be free, but they'll be a lot less expensive than if purchased through an audio dealer.
Well, I received the 1 1/2" arch punch today, and it's absolutely perfect for the job. Thanks, Stilljd, for the suggestion.

I have a few extra sets of four 1 1/2", 3/8" (not 5/8" as previously stated), 40 durometer discs available for a very reasonable price.
I have some miscellaneous pieces remaining. They are about 1/2"x1/2" and shaped like four pointed stars. Imagine a square with four circles cut out. The remaining "star" in the middle is what I have. I use a couple sets of these starfish footers under power supplies. If anyone is interested in some sets of four, I will offer them for the cost of mailing plus a small handling fee to cover the padded mailing envelope and my time to go to the Post Office. Basically, I want to get the leftover stuff out of my office, and I hate to throw it away (or store it).

These are really great tweaks, and available for less than a good deli sandwich. :)